Heater for pavement markers



May 25, 1965 H. M. PREUSSER ETAL HEATER FOR PAVEMENT MARKERS Filed April 16, 1962 5 Sheets-Sheet 1 HENRY M. PREUSS ER ERIC B. DENTON INV EN TOR.

i 1965 H. M. PREUSSER ETAL 3,185,455

HEATER FOR PAVEMENT MARKERS Filed April 15, 1962 5 Sheets-Sheet 2 HENRY M. PREUSSER ERIC B. DENTON INVENTOR.

May 25, 1965 H. M. PREUSSER ETAL 3,185,455

HEATER FOR PAVEMENT MARKERS 5 Sheets-Sheet 3 Filed April 16. 1962 FIG 5 HENRY M. PREUSSER ERIC B. DENTON FIG' FIG

May 25, 1965 H. M. PREUSSER ETAL 3,185,455

HEATER FOR PAVEMENT MARKERS Filed April 16, .1962 5 Sheets-Sheet 4 HENRY M. PREUSSER ERIO B. DEw ggl H. M. PREUSSE R ETAL 3,185,455

HEATER FOR PAVEMENT MARKERS May 25, 1965 5 Sheets-Sheet 5 Filed April 16, 1962 RY M. PREUSSER l0 8. DENTON INVENTOR.

HE ER l l l l l l l I I I g I l I FIG United States Patent r 3,185,455 HEATER FOR PAVEMENT MARKERS Henry M. Preusser and Eric B. Denton, Seattle, Wash,

assignors, by mesne assignments, to Weyerhaeuser Company, Tacoma, Wash, a corporation of Washington Filed Apr. 16, 1962, Ser. No. 187,612 3 Claims. (Cl. 263-11) This invention relates to a new, novel and useful concept in a heater for traflic markers which are to be applied to road and street surfaces and more particularly to a gas-fired immersion type heater for preheating such trafiic markers before they are applied to said surfaces.

The current trend toward the use of reflective traffic markers or buttons in place of stripe painting or other forms of channeling requires new equipment. The markers are usually made of solid, reflective,limpactresistant, plastic materials such as synthetic resins particularly epoxy or polyester type resins. These plastic markers from a semi-permanent installation calculated to function for five to twenty years. The most effective thermosetting adhesive for bonding the markers to the road surfaces is derived from epoxide resin. They produce adhesives which are thermosetting, and which when placed between the marker and road surface will set or a cure in five to ten minutes, thereby providing a bond between marker and road surface which is actually stronger than concrete. The use of a thermosetting resin adhesive is facilitated by heating the road or pavement before the adhesive is spread and the marker pressed onto the adhesive. In addition to heating the pavement it is also desirable to preheat the marker itself to insure as rapid a oms as possible. This invention is designed to preheat the markers as one of the preliminary steps to their application to the road surface.

Briefly, this invention comprises a tank designed to hold a heating liquid into which the markers are immersed in a rack or holding device. A gas-fired burner arrangement is located under the tank to maintain the liquid at the desired temperature. Appropriate elements for connecting the burners to a gas supply and for regulating gas pressure in addition to thermostatic control are supplied. This burner and its alternative embodiment are designed to be transported on a cart or on a truck.

Previously, heating the markers was accomplished in a hot air chamber. However, it was found that air heating was slower and heated the markers less .unifornily.

Accordingly, it is a prime object of this invention to provide a road marker heater which is small, compact and light and thus easily transportable.

Another object of this invention is to supply a road marker heater which is simple in design, easy and inexpensive to construct.

Yet another object of this invention is to furnish a road marker heater which heats the markers in a minimum of time as compared to other types of marker heaters.

Still another object of this invention is to provide a road marker heater which will heat the markers to any temperature within and over a wide range of temperamarker heater which has an open pot with racks or r holders therein to permit easy immersion and withdrawal of the markers from said pot.

These, together with other objects and advantages which will become subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings, forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a side elevational view of the invention with part of the side wall broken away to show the burners, heating pot and rack rotating mechanism;

FIGURE 2 is an end elevational view of this invention included to show the control guard box, stack and stack support;

FIGURE 3 is a top plan view showing the general arrangement of parts as seen from above;

FIGURE 4 is a plan view layout of the burner and burner control layout as seen from the line 4-4 in FIGURE 1;

FIGURE 5 is an end elevational view of the rotating mechanism as seen along the line 5-5 of FIGURE 1;

FIGURE 6 is a side view of the marker rack;

. FIGURE 7 is an end view of the marker rack;

FIGURE 8 is a side view of a holder for the markers as it is accommodated in the rack;

FIGURE 9 is an end view of a holder to further clarify its construction;

FIGURE 10 is a side elevational view of an alternative embodiment of this invention which does not include a rotating rack within the pot;

FIGURE 11 is a plan view of the burner layout taken along the line 11-11 of FIGURE 10;

FIGURE 12 is a top plan view of the alternative embodiment; and

FIGURES 13 to 15 show various views of the marker holders which are used in the alternative embodiment.

Referring now to FIGURES 1 to 4, it will be seen that the marker heater is comprised of a housing generally designated by number 10 having a tank generally referred to by number 12 and a burner and burner control system generally shown by number 14.

Heater housing the front and back walls 16 and 18 are vertical to the it top of the housing. However, side walls 20 and 22 about two thirds the distance to the top angle inwardly to form sloping side wall sections 24 and 26. Each sloping Wall section has a handle 28 afi'ixed thereto. Front wall 16 has a circular opening 30 near the bottom thereof to permit access to the burner elements which will be more fully described hereinafter. Said opening 30 has a round cover plate 32 pivotally secured to said side wall, as at 34, to close said opening. The cover 32 has handle 36 to swing said cover about its pivot.

Located on the bottom portion of side wall 22 are two opposed angular vents 38 extending through about arcs and covered by a plate at which also has two open ings of the same size and angularity. The plate has a handle (not shown) for rotating said plate about its center point, thus allowing the inside of the housing to be vented to the atmosphere if the wall openings and cover openings are aligned and to be closed if the solid sections of the plate are slipped over the wall vents.

The lower portion of back wall 18 is open adjacent to bottom wall 19 across the entire width of said wall. In this manner access may be had to the burner sys-. tern controls which lie outside the housing so far described. In order to give a clearer picture it must be understood that housing 10 itself is about 25 inches high. The opening in said back wall is approximately inches high. A control guard wall 42 is attached to side Walls 20 and 22 and is spaced about 5 inches from said opening so that it is formed in a substantially shallow U-shape. Said guard also has floor 44 and is open on top.

Above the control guard near the level at which the sloping side wall sections 24 and 26 join the side walls 20 and 22 is located an enclosed stack support box 47 having top 52, bottom 48, ends 46 and back 51). The support box 47 measures approximately 3 inches deep from top to bottom and extends about 6 inches rearwardly from back wall 18. FIGURE 1 shows that two openings 54 vent the inside of said housing to said box 47. Each opening 54 is generally located near a side wall substantially beneath the sloping side wall sections 24 and 26. Thus, said openings are located adjacent the ends 46 of said box 47. An oval stack 56 is placed on top wall 52 and opens into box 47, said stack being about 18 inches long thus making the overall height of this marker heater about 35 inches. The stack, of course, is centered between the ends of box 47 and is further supported by a channel shaped stack brace 58 secured between said stack 56 and said back wall 18.

Near the front end of sloping side wall section 24 is located an elongated rectangular opening extending generally parallel to the edge of said wall section 24 and front wall 16. Said opening is in excess of 1 inch Wide and in excess of 5 inches long. A semi-circular upstanding guard is secured over the opening and is about 3 inches high and as wide as the opening. Said guard 60 has a generally horizontal channel guard 62 extending from front to rear of the housing. Said channel guard 62 covers the lower end of the opening and also opens into said upstanding guard 60. Both guards 60 and 62 are provided to protect the thermostat tube which runs from the bulb located in the tank, through or under said guards and down the back side of the heater to the thermostatically operated valve located at the bottom of the heater and within the control guard wall enclosure 42.

The inside surfaces of housing 10 are lined with a half inch thickness of insulation except of course where there are vents or openings or where there may be parts of the pot projecting to prevent such lining. The upper edges of walls 16, 18, 24, and 26, have /2 inch horizontal inside flanges 64 thereon, thus defining an unobstructed opening approximately 12 by 16 inches. The tank assembly, which will be described more fully hereinafter, is supported on said flanges 64.

Burners land burner controls FIGURES 1 and 4 illustrate the burner arrangement 14 and the manner in which the burners are controlled. A fuel inlet coupling 66 protrudes from one side of the open control area above guard wall 42 to receive a hose or line from the fuel supply tank (not shown). From coupling 66 fuel is directed through an appropriate line or conduit to a pressure regulator 68 which is calibrated to introduce fuel into the burner system at a pressure of about inches of water. From regulator 68 the fuel is directed to an on-otf valve 70 also located in the control area. A thermostatically operated valve 72 is also located in the central area and is connected by piping to the outlet side of valve 70. From thermostatically operated valve 72, the fuel is converged to the inside of housing 10. The burners are located beneath the tank 12 and comprise three U-shaped headers 74. Each header 74- has a plurality of burner nozzles 76 angled inwardly from the header legs. The base end of each U-shaped header 74 faces the control area. A main supply and support pipe 78 runs from thermostat 72, into housing 10 and extends along or over a substantial part of the width of said housing. The base end of each header 74 is connected by a branch support pipe 80 to the main supply and support pipe 78. It is on the branch pipes 80 that the headers are supported, said branch pipes being in turn supported on pipe 78. It will be noted, by reference to FIGURE 1, that the two outside headers are placed higher than the middle header in order to compensate for the curvature of the bottom of tank 12. In this positioning of the burners heating of tank 12 can be more closely controlled.

A pilot jet 82 is attached to the middle header and has a fuel supply line 84- running therefrom to the valve 70 in the control area.

H eating tank and rotating rack assembly FIGURES 1 and 5 to 7 show the essential details of the preferred embodiment of the tank, the rotating rack and its actuating mechanism. Tank 12 is rectangular at the top thereof having fiat, U-shaped front wall 86 and back wall 88. Side walls 90 and 92 join said front and back walls and rounded bottom wall 94 is joined to the lower U-shaped configuration of said front and back walls. Attached to the bottom of said tank near back wall 88 is a drain spout 96 having a valve (not shown) for opening and closing said spout.

A small diameter rod 98 of perhaps 7 inch dimension is anchored at the junction of bottom wall 94 and front wall 86 about halfway between the bottom of the tank and the bottom of side wall 92. Said rod is spaced perhaps inch from the inside surface of front wall 86 and angles toward the lower portion of side wall 92. Said rod is about 10 inches long and thus extends to within 4 or 5 inches of the bottom portion of said side wall 90. A coupling 11%) is rigidly anchored in the lower portion of side wall 96 generally in line with rod 98, that is, quite close to the seam between front wall 86 and side wall 90. Coupling 100 permits the insertion of a thermal element for thermostatically operated valve 72 into the tank. Since the thermal element is of the helical coil type it may be held in place by rod 98 by simply sliding said element on said rod so that the rod is received up through the center of said coil element. Coupling 100 can be seen to be connected to side wall 90 at a slight (about 15) angle to the horizontal.

The inside surfaces of the tank back wall 88 and front wall 86 have fixedly secured thereto a journal bearing 102 at the approximate center point of the radius of curvature of semi-circular or round bottom 94. Said bearings 182 have as their function to support the shaft of the rotating rack now to be described.

As can be seen in FIGURES 6 and 7 the rack, generally referred to by number 104 is comprised of a pipe shaft 106 which supports the rack on bearings 102 and which is the means by which the rack is rotated in the tank. A large diameter tube 110 concentrically surrounds shaft 186 and is slightly shorter in length than said shaft 106. Said tube 110 is rigidly secured to shaft 106 by circular spacer plates 108.

The rack tube 119 is provided with 8 pairs of spokes 112 which are fabricated at one end to conform to the radius of curvature of tube 111). The pairs of spokes are welded one to each end of the tube so that each pair is aligned along the length of the tube. The spokes are placed on said tube at equispaced points. Supported between and attached to each pair of spokes 112 is a divider wall 114 having holes 116 cut therein. Assembly of the various parts of the rack is made with welds. Holes 116 are provided in wall 114 to reduce the resistance of the rack as it is rotated in the tank full of heating fluid. The eight pairs of spokes and eight plates form eight compartments on the rack.

The mechanism for rotating rack 104 is pictured in FIGURES 1 and 5. Basically, said mechanism 120 is comprised of a mounting plate 122 which is attached to the inside surface of the tank wall. Said mounting plate 122 is outwardly flanged at its top and tapers from a width of about 5% inches to a width of perhaps 4 inch over a length of about 8 inches. A top half bearing 124 is secured to the small end of said mounting plate and is adapted to fit over the end of pipe at and rigidly attached the top of the mounting plate and houses a sprocket 132 over which chain 127 passes. Said guard is so designed that it boxes in the sprocket 132 on the top and sides and ends but is open at the bottom thereof to permit chain 127 to connect to said sprocket. A tube or sleeve 130 is secured to the outer side of guard 128. An appropriate hole is provided in the guard to permit a shaft 134 to extend through said sleeve and into the interior of said guard, said shaft 134 being the means by which sprocket 132 is mounted within said guard. A crank arm 138 is attached to the outer end of shaft 134 and said crank arm is provided with a handle 140. It will be noted that a circular guide plate 136 is fixedly mounted on sleeve 130 in spaced relation to arm 138. Said plate is provided with holes 142, one of which is located at the top of said plate and the other at the bottom thereof diametrically opposite said top hole. The axis of each hole 142 is aligned with the axis of handle 140. The handle is provided with a spring loaded pin 144 which is received in said holes to hold the rack 104 steady. When it is desired to move the rack the handle is pulled back against the force of a spring and the pin is withdrawn from a hole. When the handle is swung through an arc of 180 the pin then reseats itself in the next'hole until withdrawn again.

Sprocket 132 located in guard 128 is small. A larger sprocket 126 is securely mounted on one end of pipe shaft 106 (see FIGURE 7) so that it is in the same plane as sprocket 132 and connected thereto by chain 127. The 180 movement of handle 140 together with the ratio of gear teeth on sprockets 132 and 126 moves the rack A: of a full revolution. In this manner each 180 movement of the handle advances the rack a compartment at a time. Top bearing 124 prevents the chain from lifting rack 104 off journal bearing 102. i

The buttons or markers are immersed in tank 12 by virtue of holders generally shown by number 150 (see FIGURES 8 and 9), which are inserted into the compartments of rack 104. Each holder 150 is comprised of an inverted U-shaped strap 152. The free ends of said strap 152 are jointed by an L shaped base support 154 with the open part of said L facing away from the web portion of said strap. A rectangular bar 156 is attached to the outside of each leg of strap 152 and /3 the distance from the web to the end of said legs. Bar 156 is connected to said strap 152 to one side of its center point. Bar 156 is a flat sheet material on three sides. The remaining side is L shaped with the open angle facinginwardly. The bar 156 is mounted at about a 70 angle to the strap. Thus, the holder takes the shape of a simple cage. Since the strap and the bar are attached to each other at an angle an opening is provided by which the round road markers 158 may be inserted into the holder. The markers themselves are flat on one side and convex on the other, thus having a cookie shape. It is contemplated of course that the markers may assume any desired shape or configurations. As can be seen in FIGURES 8 and 9, the holder is of such dimensions that it slips into the compartments on the rack. Holder 150 is so dimensioned that two of such holders will be received into each rack compartment in side-by-side position, with each holder supporting 6 markers. a V

The web of strap 152 has a bearing 160 secured to the outside surface thereof. As loaded holders are inserted into the compartments and the rack rotates, bearing 160, which may be made of nylon, Teflon or other suitable bearing material, comes to bear on the tank walls thus eliminating metal to metal contact between holder and tank. The cagelike nature of the holder, of course, permits the fluid to circulate freely around the markers to heat them to the desired temperature. When a holder full of heated markers is removed from the rack the liquid runs ofi freely.

The tank 12 is constructed to hold about 5 gallons of heating fluid. As a holder which has been moved through a full 360 rotation of the rack is removed and the heated markers taken therefrom, cold markers are placed in the holder. The reloaded holder is then reinserted in a com partment and the cycle is repeated.

An alternative embodiment of this marker heater is shown in FIGURES 10 to 15. This alternative embodiment has a rectangular tank portion 170 having handles 172 attached to each end thereof. The tank is about 9 inches deep by about 10 inches wide by about 14 inches long. A base portion generally shown by number 174 and attached to the lower section of tank 170 supports said tank so that its bottom wall is about 8 inches above the ground. Said base portion 174 comprises a back wall 176, and side walls 178 and 180. The base covers a portion of each end of the front to form front base strips 182 and 184. Thus an opening is defined in the front wall of the base to permit access to the area beneath the heater tank 170. Simple hinge devices 186 are attached to base strips 182 and 184 to support a swinging door 188 which extends slightly more than halfway from the top of said opening to the ground. Said door 188 is provided to permit access to the burners. A rectangular opening 1% is cut in back wall 176 and is approximately 3 by 8 inches with the upper edge thereof near the tank bottom. Said opening allows fumes and smoke from the burners to escape to the atmosphere. Covering said opening 190 is a stack support box 192 which is constructed onto the outside of back base wall 176 and into which said opening leads. A stack 194 is secured to the top of said box with an opening in said top completing the passage by which fumes and smoke are exhausted from the enclosed burner area beneath the tank.

An outlet 1% is located at the bottom of the tank wall for draining fluid from said tank. It will in practice, of

course, be provided with a shut off valve (not shown). Another port or orifice 198 is provided in the front wall of said tank 174 near the bottom and close to one side Wall. Said orifice 198 is provided with a coupling for receiving a thermo bulb which will be attached by a capillary tube to a thermostatically operated valve. The bulb of course will extend into the tank.

The burner and burner control system, generally shown by the number 200, are situated in the space beneath tank 170. Fuel enters the burner system through a hose 202 from a source such as a propane bottle. Hose 202 is detachably connected to an appropriate inlet coupling on the pressure regulator 204 which adjusts the fuel flow to about 20 inches of water. A line 206 carries the fuel to thermostatically operated valve 210. A snap-on type coupling 208 is inserted in the line 206 between regulator 204 and thermostatically operated valve 210. Said snap-on type coupling is positioned so that the adapter end thereof protrudes from under the swinging door 188 out beyond the wall line of the tank and base. Similarly the adjustment knob for thermostatically operated valve 210 also protrudes out from under the lower edge of said swinging door. The fuel travels from thermostatically operated valve 210 to gas service (on-off) valve 212, and from valve 212 to a U-shaped header 214 which has a series of jets 216 located on the upper surface thereof. The jets 216 of course permit an even distribution flame beneath the tank to vkeep the marker heating fluid in said tank at the proper temperature. It should be mentioned that snap-on type coupling 208 is provided for purposes which are not important to an, understanding of this invention, since it has to do with equipment used in conjunction with this heater.

,The burners and burner controls may be supported in any-desirable manner beneath the tank. For instance straps 218 attached to the inner surface of side Walls 17 8 and 180 may provide the primary means of support for said system.

Holders, generally referred to by number 220, are provided to receive the road marker-s. A cylindrical casing 222 which is open at both ends comprises the main body of the holder. A portion of the casing wall is cut out along the length thereof to permit hand grasping of the markers as they are stacked within the casing. Facing the open portion 226 of the casing wall, i.e., situated diametrically opposite said opening 226, is a handle 224 which is welded or otherwise secured to the upper outside surface of said casing. Said handle extends upwardly above the top of said casing and is bent at the tip thereof in the direction of the opening 226. A bottom strap 223 extends across the bottom of said casing to effectively retain the markers Within the casing but Without closing said bottom. The holders 220 are of such dimensions that six holders may be accommodated in the tank 170. The nature of the holders is such that when one is placed in the tank the heating fluid is free to circulate around the markers thus raising said markers to the temperature needed for their application to a road surface. When the holders are lifted out of the tank the liquid is free to run off.

The foregoing is considered as illustrative only of the principle of this invention. Since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling Within the scope of the invention.

What is claimed is:

1. A heater for pavement markers, comprising: a boxlike heater housing; a liquid receiving tank supported in the upper portion of said heater housing, said tank having a semi-circular bottom wall structure and including a rotating rack mechanism therein for holding said pavement markers; burner means located beneath said tank and within said housing; fuel conduit means located beneath said tank and adapted to receive fuel for said burners from a source external to and independent of said heater housing and to convey said fuel to said burner means; a control system for said burner means and said fuel conduit means; and an exhaust stack attached to said housing, there being means for venting the housing area beneath said tank to said exhaust stack.

2. A heater for pavement markers, comprising: a rectangular, box-like heater housing; a liquid receiving tank supported in the upper portion of said heater housing, said tank having a semi-circular bottom Wall structure and including a rotating rack mechanism therein for holding said pavement markers; burner means located beneath said tank and Within said housing; fuel conduit means located beneath said tank and connected to said burner means, said fuel conduit means being adapted to receive fuel for said burners from a source external to and independent of said heater housing and to convey said fuel to said burner means; a control system for said burner means and said fuel conduit means, said control system including a thermostatically operated valve, a fuel pressure regulator and a shut-oil valve; and an exhaust stack attached to said housing, there being means for venting the housing area beneath said tank to said exhaust stack.

3. A heater for pavement markers, comprising: a boxlike heater housing; a liquid receiving tank supported in the upper portion of said heater housing, said tank having a semi-circular bottom wall structure and including a rotating rack mechanism therein for holding said pavement markers, said tank having attached thereto an actuating means for said rack mechanism, said actuating means including a turning handle and drive sprocket at the top of said tank connected to a driven sprocket on said rack mechanism by a chain means; burner means located beneath said tank and within said housing; fuel conduit means located beneath said tank and connected to said burner means, said fuel conduit means being adapted to receive fuel for said burners from a source external to and independent of said heater housing and to convey said fuel to said burner means; a control system for said burner means and said fuel conduit means, said control system including a thermostatically operated valve, a fuel pressure regulator and a shut-off valve; exhaust stack means attached to said housing, there being means for venting the housing area beneath said tank to said exhaust stack means; and open, cage-like marker holder means in said tank for supporting pavement markers in the liquid in said tank.

References Cited by the Examiner UNITED STATES PATENTS 646,946 4/00 Blair et al 126--345 812,546 2/06 Cloninger 126346 1,185,811 6/16 Long 126-345 1,670,931 5/28 Daniels 126345 2,552,621 5/51 Clay 99404 2,943,850 7/60 Moseley 263l9 2,967,474 1/ 61 Ford 99404 FOREIGN PATENTS 221,249 9/ 24 Great Britain. 456,164 11/36 Great Britain.

CHARLES SUKALO, Primary Examiner.

JOHN J. CAMBY, PERCY L. PATRICK, Examiners. 

1. A HEATER FOR PAVEMENT MARKERS, COMPRISING: A BOXLIKE HEATER HOUSING; A LIQUID RECEIVING TANK SUPPORTED IN THE UPPER PORTION OF SAID HEATER HOUSING, SAID TANK HAVING A SEMI-CIRCULAR BOTTOM WALL STRUCTURE AND INCLUDING A ROTATING RACK MECHANISM THEREIN FOR HOLDING SAID PAVEMENT MARKERS; BURNER MEANS LOCATED BENEATH SAID TANK AND WITHIN SAID HOUSING; FUEL CONDUIT MEANS LOCATED BENEATH SAID TANK AND ADAPTED TO RECEIVE FUEL FOR SAID BURNERS 